When did humans get smart? Maybe a lot earlier than some thought.
A find in South Africa suggests that humans had mastered the skill of producing small stone blades – and could pass on the know-how – as early as 71,000 years ago.
Small stone blades found in a cave along a rugged stretch of South Africa's coast have pushed back by thousands of years evidence for persistent, advanced stone-toolmaking skills in early modern humans, according to a new study.
The results suggest that by 71,000 years ago, these people had long since developed the mental horsepower to tackle production problems and pass their manufacturing techniques to subsequent generations – a lot earlier than some researchers had thought.
Indeed, to some scientists the find supports the idea that mental abilities associated with modern humans emerged when anatomically modern humans did, about 200,000 years ago, rather than resulting from a genetic mutation cropping up between 40,000 and 50,000 years ago, as others have posited.
The evidence comes in the form of a large number of stone blades that average about one inch long. The blades were excavated from successive layers in soil deposits some 46 feet thick in a cave at Pinnacle Point, on the coast some 210 miles east of Cape Town. The deposits span some 18,000 years.
The oldest bladlets were found in a layer dated to 71,000 years ago and continued to appear in layers representing the ensuing 11,000 years. The same technique was used to prepare the parent stones throughout the period, but the designs evolved over time according to the international team reporting the results in Thursday's edition of the journal Nature.
Pinnacle Point boasts "a very impressive record" of advanced cognitive abilities in early modern humans at the time period the site covers, says Rick Potts, director of the human origins program at the Smithsonian Institution's Museum of Natural History in Washington.